| 41. |
- Askarieh, Glareh, et al.
(författare)
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Self-assembly of spider silk proteins is controlled by a pH-sensitive relay
- 2010
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Ingår i: Nature. - : Springer Nature. - 0028-0836 .- 1476-4687. ; 465:7295, s. 236-8
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Tidskriftsartikel (refereegranskat)abstract
- Nature's high-performance polymer, spider silk, consists of specific proteins, spidroins, with repetitive segments flanked by conserved non-repetitive domains. Spidroins are stored as a highly concentrated fluid dope. On silk formation, intermolecular interactions between repeat regions are established that provide strength and elasticity. How spiders manage to avoid premature spidroin aggregation before self-assembly is not yet established. A pH drop to 6.3 along the spider's spinning apparatus, altered salt composition and shear forces are believed to trigger the conversion to solid silk, but no molecular details are known. Miniature spidroins consisting of a few repetitive spidroin segments capped by the carboxy-terminal domain form metre-long silk-like fibres irrespective of pH. We discovered that incorporation of the amino-terminal domain of major ampullate spidroin 1 from the dragline of the nursery web spider Euprosthenops australis (NT) into mini-spidroins enables immediate, charge-dependent self-assembly at pH values around 6.3, but delays aggregation above pH 7. The X-ray structure of NT, determined to 1.7 A resolution, shows a homodimer of dipolar, antiparallel five-helix bundle subunits that lack homologues. The overall dimeric structure and observed charge distribution of NT is expected to be conserved through spider evolution and in all types of spidroins. Our results indicate a relay-like mechanism through which the N-terminal domain regulates spidroin assembly by inhibiting precocious aggregation during storage, and accelerating and directing self-assembly as the pH is lowered along the spider's silk extrusion duct.
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| 42. |
- Backius, Stefan
(författare)
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Arbetare på scen : amatörteater som politiskt verktyg
- 2011
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis focuses on the political dimensions of aesthetic expression during the Long Sixties. The thesis deals with amateur theatre ventures both within and linked to the social democratic labour movement. ’Spelet om Norbergsstrejken’ (The Play about the Norberg Strike) had its première in 1977 in a small industrial village in the industrial region of Bergslagen. Similar plays appeared in many regions of the country and a wave of workers’ plays emerged and made an impact on the internal investments of the educational association ABF in amateur theatre. The empiricism of the thesis concludes in 1982 when a social democratic amateur theatre association was founded and after a breakaway from the social democratic movement was establishing a residential study centre in another small village in Bergslagen. Sixties radicalisation provides the social context of the study and the perspective of sociological social movement research is used and developed. Based on the perspective of cognitive practice and the concepts of cosmology and movement ideology attention is directed towards the theatre assets of performance hosts, expectation horizons and patterns of behaviour. The thesis argues for a deeper understanding of sixties radicalisation partly meaning that the periodisation needs to be extended backwards as well as forwards in terms of time and partly that the political dimensions of aesthetic expression should be focused on. Based upon the results of the thesis the concept of culturactivism was formulated which defines the specific approach that appeared in the space between political and cultural activism. This highlights the need for a concept that covers the cognitive free space that arose between aesthetic expression and political activism and which has not previously attracted the attention of historical studies about sixties radicalisation to any great degree.
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| 43. |
- Bashkanov, M., et al.
(författare)
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WHAT IS THE NATURE OF THE ABC EFFECT?
- 2011
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Ingår i: International Journal of Modern Physics A. - 0217-751X .- 1793-656X. ; 26:3-4, s. 627-629
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Tidskriftsartikel (refereegranskat)abstract
- The ABC effect - an intriguing low-mass enhancement in the pi pi invariant mass spectrum - is known from inclusive measurements of two-pion production in nuclear fusion reactions. Exclusive measurements have been carried out at CELSIUS/WASA and WASA-at-COSY for the fusion reactions leading to d, (3)He and (4)He. They all reveal this effect to be of isoscalar nature and associated with a narrow Lorentzian-shaped structure in the total cross section. The latter could point to the formation of an isoscalar resonance, which couples to the pn channel as well as to an intermediate Delta Delta state.
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| 44. |
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| 45. |
- Berlowski, Marcin, et al.
(författare)
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SEARCH FOR EXOTIC EFFECTS IN eta MESON LEPTONIC DECAYS
- 2011
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Ingår i: International Journal of Modern Physics A. - 0217-751X .- 1793-656X. ; 26:3-4, s. 630-631
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Tidskriftsartikel (refereegranskat)abstract
- The search for the decay eta -> e(+)e(-) was carried out using the WASA detector at the COSY storage ring. Data were taken during a two week experimental run in Sept-Nov 2008 in which about 10(7) eta mesons were collected from the reaction of pp -> pp eta at energy of 1.4 GeV. Background studies were performed for several different reactions. The performance of the WASA detector for the measurement of electron-positron pairs based on the single Dalitz decay of the eta meson was studied. We also identified a statistically significant data sample of other more frequent leptonic decays.
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| 46. |
- Bertlett, Johan, et al.
(författare)
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A two-way approach of congruent behavior between leaders and staff in the employeeship concept: Test of model, questionnaires, and influence on climate
- 2012
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Ingår i: Leadership & Organization Development Journal. - : Emerald. - 1472-5347 .- 0143-7739. ; 33:5, s. 428-446
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Tidskriftsartikel (refereegranskat)abstract
- Purpose – The authors have developed the Leadership-Employeeship-Relationship Model and a questionnaire following their conceptualization of the employeeship concept. It is possible to separately study leadership, peer employee, and interactive leader-follower behaviors. The purpose of this paper is to examine the relationship between the conceptualization and operationalization, as well as between the model and psychological climate. Design/methodology/approach – In total, four organizations operating at an airport participated. The quantitative approach involved data gathered from expected leadership and employee behaviors and psychological climate attitude questionnaires. The leadership and peer employee variables are separately based on the leadership and employeeship questionnaires, whereas the leader-follower variable is based on the results of both questionnaires. All analyses were made on the variable level. Findings – The results show that expected leadership, peer employee, and congruent leader-follower behaviors all have a positive correlation with psychological climate. Hierarchical regression analyses indicated that congruent leader-follower behavior had augmented value to leadership behavior and its relationship to psychological climate. Practical implications – Congruent leader-follower behavior plays an important role in the overall improvement of psychological climate. Steps toward congruent behavior are to allow followers to participate in leadership development and that the issue of shared responsibilities and authority is best managed in collaboration between management and staff. Originality/value – The paper is the first to demonstrate empirically the relation between the interactive leader-follower employeeship perspective based on the expected behaviors of both leaders and followers and psychological climate.
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| 47. |
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| 48. |
- Bi, Dongqin, et al.
(författare)
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Efficient and stable CH3NH3PbI3-sensitized ZnO nanorod array solid-state solar cells
- 2013
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Ingår i: Nanoscale. - : Royal Society of Chemistry (RSC). - 2040-3364 .- 2040-3372. ; 5:23, s. 11686-11691
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Tidskriftsartikel (refereegranskat)abstract
- We report for the first time the use of a perovskite (CH3NH3PbI3) absorber in combination with ZnO nanorod arrays (NRAs) for solar cell applications. The perovskite material has a higher absorption coefficient than molecular dye sensitizers, gives better solar cell stability, and is therefore more suited as a sensitizer for ZnO NRAs. A solar cell efficiency of 5.0% was achieved under 1000 W m(-2) AM 1.5 G illumination for a solar cell with the structure: ZnO NRA/CH3NH3PbI3/spiro-MeOTAD/Ag. Moreover, the solar cell shows a good long-term stability. Using transient photocurrent and photovoltage measurements it was found that the electron transport time and lifetime vary with the ZnO nanorod length, a trend which is similar to that in dye-sensitized solar cells, DSCs, suggesting a similar charge transfer process in ZnO NRA/CH3NH3PbI3 solar cells as in conventional DSCs. Compared to CH3NH3PbI3/TiO2 solar cells, ZnO shows a lower performance due to more recombination losses.
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| 49. |
- Bill-Axelson, Anna, et al.
(författare)
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Radical prostatectomy versus watchful waiting in early prostate cancer.
- 2011
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Ingår i: The New England journal of medicine. - : Massachussetts Medical Society. - 1533-4406 .- 0028-4793. ; 364:18, s. 1708-17
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Forskningsöversikt (refereegranskat)abstract
- In 2008, we reported that radical prostatectomy, as compared with watchful waiting, reduces the rate of death from prostate cancer. After an additional 3 years of follow-up, we now report estimated 15-year results.
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| 50. |
- Birk, Wolfgang, et al.
(författare)
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Interactive modeling and visualization of complex processes in pulp and paper making
- 2010
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Konferensbidrag (refereegranskat)abstract
- This paper discusses a new approach to interactive modeling, visualization and analysis of complex industrial processes. A theoretical framework based on signal flow graphs for modeling and visualization is presented. Using this framework a software tool is designed, called ProMoVis, which can be used to model a process, to visualize the models together with process construction and control system, and to perform analysis regarding e.g. feasible control strategies for the process. Moreover, a case study is conducted, where ProMoVis is used to model, visualize and analyze a stock preparation plant. The results indicate that the proposed methods and tools improve work flows, increase process understanding and simplify decision making on control strategies for complex process.
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